A project manager has been asked to provide an explanation regarding a $2,220 favorable material variance on a playground equipment project. After further analysis, the project manager was able to break down the material variance to an unfavorable price variance of $1,700 and a favorable quantity variance of $3,920. The best explanation of the variances is that the A. Human resources department failed to hire adequately trained workers, causing materials to be wasted. B. Purchasing department purchased a higher quality material, resulting in less wasted materials. C. Decision by the purchasing department to use a new supplier resulted in the purchase of the materials for a lower price. D. Excellent scheduling by the production department enabled the purchasing department to reduce shipping costs.